Total monetary value of bonuses applied for by A divided by the total monetary value of bonuses applied for by A and B. That way B is less successful because she's missed 83% of available bonuses compared to A's 16%. As said above, I'm not sure this can be well expressed in a simple stat.

Secondly, it’s not always a bonus, it’s an increment on your salary and these are a % jump so are also variable. To confuse matters more, you can get both an increment and a bonus. You can also apply twice – Once as a team application and once as an individual.

Therefore I think concentrating on what value of awards they missed out on is not the way forward. ?

Is there an upper limit to the performance-based bonus and the salary increment? And do you want the bigger bonuses to be more important than the smaller ones (e.g. Person A getting one massive bonus looks better than Person B getting 5 smaller ones)?

Require:
length of time during which these applications took place
whether this was the actual bonus bonus or just the incremental wage increase bonus (two different things really)
how long A and B have been employed

In order to more equally compare the two and be able to see what correlation lies between the two sets of rejections you're going to have to give more information.

A person applies for a bonus. They get rejected. Presumably they got rejected cos they weren't good enough, or the company wasn't. And then that's all in the past. There's no accumulated 'unfairness' that needs to be accounted for when they next apply for a bonus. Their application for the next bonus is judged on its merits in relation to the relevant preceding period.